Aircraft are highly complex machines that operate under a variety of extreme conditions of temperature, precipitation, pressure, vibration, etc. One important component of any aircraft is its electronic control and power distribution systems, which are often provided by using many kilometers of wiring provided behind various sealed wall and fuselage panels.
Wiring in aircraft can be critical to proper operation and regular checks and maintenance are essential to ensure that wires subject to aging, accidental damage caused during maintenance, vibration or rubbing against other wires during flight, getting bent, getting wet, stamped on, etc., are serviceable and not dangerous.
To aid in checking the condition of such aircraft wiring various fault detection and location devices, such as circuit breakers, etc., are known for use in aircraft [1-3]. However, these conventional devices do not necessarily detect or prevent certain difficult to detect wiring faults, such as arcing, which may only occur intermittently and in an unpredictable manner.
Arcing may be particularly dangerous, for example, where it creates sparks that then cause ignition of combustible materials. Indeed arcing has been associated with various air accidents: e.g. in July 1996 when TWA 800 exploded mid-air near New York killing all persons on board and in September 1998 when Swissair 111 endured a cockpit fire and subsequently crashed into the sea also killing all on board. In both cases, faulty wiring that caused subsequent arcing is believed to be at the root of the accident.
Given the potential dangers associated with arcing, various arc detection systems have therefore been developed [4-8]. However, whilst such arc detection systems are an improvement upon previous fault detection and location devices [1-3], there remains the problem of accurately locating the position of faults that cause arcing, especially for intermittent arcs where there is no easy access to a wire or wire bundle that needs to be tested (e.g. where such wires are embedded behind aircraft panels and are out of reach).
The present invention has thus been devised whilst bearing the above-mentioned drawbacks associated with conventional techniques in mind.